package cn.mrerror.one.utils.cdn.tencent.lib;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.security.MessageDigest;

public class SHA1 {

    public static String stringToSHA(String str) {

        try {
            byte[] strTemp = str.getBytes();
            MessageDigest mdTemp = MessageDigest.getInstance("SHA-1"); //SHA-256
            mdTemp.update(strTemp);
            return toHexString(mdTemp.digest());
        } catch (Exception e) {
            return null;
        }
    }

    public static String fileNameToSHA(String fileName) {
        InputStream inputStream = null;
        try {
            inputStream = new FileInputStream(fileName);
            return streamToSHA(inputStream);
        } catch (Exception e) {
            return null;
        } finally {
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    public static String streamToSHA(InputStream inputStream) {
        try {
            MessageDigest mdTemp = MessageDigest.getInstance("SHA-1"); //SHA-256
            byte[] buffer = new byte[1024];
            int numRead = 0;
            while ((numRead = inputStream.read(buffer)) > 0) {
                mdTemp.update(buffer, 0, numRead);
            }
            return toHexString(mdTemp.digest());
        } catch (Exception e) {
            return null;
        }
    }

    private static String toHexString(byte[] md) {
        char hexDigits[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
                'a', 'b', 'c', 'd', 'e', 'f'};
        int j = md.length;
        char str[] = new char[j * 2];
        for (int i = 0; i < j; i++) {
            byte byte0 = md[i];
            str[2 * i] = hexDigits[byte0 >>> 4 & 0xf];
            str[i * 2 + 1] = hexDigits[byte0 & 0xf];
        }
        return new String(str);
    }
}
